WLP represents a rapidly growing market segment due to the need for high-density, high-pin-count, smaller size, stacked and high performance devices. This growth gives rise to new metrology challenges with re-distribution and under bump metallization film stacks. In addition, lead-free bumps also require in-line control of material composition.
Bruker stands uniquely qualified to address these continually evolving metrology needs with industry-leading small spot, high speed X-ray Fluorescence technology.
As bond pads are getting smaller, the deposited amount of solder and the spatial distribution are an increasingly more complicated to analyze. Micro-XRF allows with spot sizes in the range of a few tens of micrometers to measure solder composition on bond pads down to 30 µm. When there is overlap of lower energetic lines, the determination of of composition can be challenging. But not with micro-XRF because it measures the high energy K-lines when determining the composition. Bruker's unique micro-XRF solutions allows investigating small areas with XTrace detector for SEM, and investigate large areas with M4 TORNADO the benchtop micro-XRF.
Explore further application examples on our Application notes: